A 75-year-old man with intermittent shortness of breath has several atrial ectopic beats on an ECG and multifocal atrial tachycardia on 24-hour Holter monitoring. What is the significance of these findings?
- Multifocal atrial tachycardia is a paroxysmal rapid atrial rhythm with at least three different P-wave morphologies (frequent premature atrial complexes) and an irregular P–P interval.
- Multifocal atrial tachycardia occurs in older patients with multiple medical problems, especially significant cardiac and respiratory disease, and confers an increased risk of AF.
- More than 30 premature atrial complexes an hour (‘excessive supraventricular ectopic activity’) are also associated with an increased risk of AF.
- Asymptomatic AF must be actively managed to prevent stroke, and this requires appropriate anticoagulation with either warfarin or a novel oral anticoagulant.
- The most important contraindications to use of beta blockers are severe bradycardia and hypotension and acute asthma; other risks include exacerbating peripheral vascular disease and masking severe hypoglycaemia in patients with unstable diabetes.